Add 21/30 and 5/8
21/30 + 5/8 is 53/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 8 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 30 × 4 = 120,
21/30 = 21 × 4/30 × 4 = 84/120 - Likewise, for the 2nd fraction, since 8 × 15 = 120,
5/8 = 5 × 15/8 × 15 = 75/120 - Add the two like fractions:
84/120 + 75/120 = 84 + 75/120 = 159/120 - 159/120 simplified gives 53/40
- So, 21/30 + 5/8 = 53/40
In mixed form: 113/40
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